Hook-jaw centering means for pipe wrenches



June 8, 1954 c. E. WRIGHT HOOK-JAW CENTERING MEANS FOR PIPE WRENCHESFiled Oct. 12, 1951 r v 0 0 0 0 o v o 0 Q 0 o o 0 o 0 5320202 1 3940 1.F I INVENTOR. j CLYDE E. WEIGHT H/S A TTOENEY Patented June 8, 1954UNITED STATES PATENT OFFICE HOOK-JAW CENTERING llIEANS FOR PIPEVVRENCHES Clyde E. Wright, Elyria, Ohio, assignor to The Ridge ToolCompany, Elyria, Ohio 2 Claims.

-ment of the hook jaw laterally towards and away from the heel jaw, tocenter the hook jaw in its housing on the handle by means of springs.Since the hook jaw must also slide longitudinally, the use of suchsprings has necessitated provision of a stationary guide of some sortagainst which the spring can .press to hold the jaw in place. One suchtype of guide and spring arrangement is illustrated in U. S. Patent No.1,727,623 to William O. Thewes.

The Thewes device has proved useful, but certain disadvantages in itsuse have appeared. These disadvantages were primarily incurred in theassembly of the device. At such times, the three tongues which formedthe internal spring of the device frequently were misaligned, causingdifficulty in the assembly and frequent rejection of the spring membersas unsatisfactory.

By my invention, I have improved this type of spring so that rejectionsfor mis-alignment of the spring tongue are reduced to practicallynothing, and also assembly of the device is made much more easy. This isaccomplished by an expedient which causes almost no increase in the costof manufacturing the device.

A fuller understanding of the invention may be had by reference to thefollowing description and the drawings which form a part of thisspecification.

Fig. i is a perspective View of the combined spring and guide memberembodying my invention;

Fig. 2 is a front elevational view thereof;

Fig. 3 is a side view partly in section of a Wrench utilizing the springand guide member;

Fig. 4 is a top plan view of the spring guide member alone;

Fig. 5 is a horizontal cross-section taken along the line 55 of Fig. 3.

As stated above, my invention has particular adaptation to use in pipewrenches. As best shown in Fig. 3, the device of my invention comprisesa combined spring and guide member Hi disposed in the opening II in thehousing 12 on the handle I3 of a pipe wrench. A hook jaw I4 is slidablydisposed in that opening and is adjusted longitudinally toward and awayfrom a heel jaw I 5 by means of a nut it that is threaded on the shankof the hook jaw and engages the lower end of the housing 12. The hookjaw 14 is held centered in the opening 1 l by a combination of twosprings. The first of the springs includes a member I ii, and the otheris a small compression coil spring 59 disposed in a recess 29 in thehousing 52 and which cooperates with the member Hi to provide thedesired action or support for the hook jaw.

The member ii) is formed with a body part that embraces the stem part 22of the hook jaw. One side 23 is in the form of long rectangle slightlycurved transversely to provide a close conformation to the shank 22 ofthe jaw. From this side, a spring tongue 58 is struck from a centralregion of the rectangle leaving metal on all sides of the opening leftby the tongue. This formation is very important. In the prior device,three tongues were formed at this stage. The outer two were supposed tobe in alignment, but very frequently they spread apart so far that theycould not be assembled into the opening ll. Moreover, if one was bent inthe direction of the spring tongue is more than the other, the load onthe two tongues was unevenly distributed and there was a tendency of thehook jaw M to become twisted in its opening i I. All of thesedisadvantages are eliminated by striking the tongue from the centralpart of the rectangle. At the same time, no additional disadvantages areincurred. By this construction the dimensional tolerances may be heldwithin closer limits, and the manufacturing problem is greatly lessenedbecause there are no plurality of tongues to become bent in variousdirections causing the disadvantages previously stated.

Extending from the rectangular side 28 is a narrow strap part 25 whichlies along the broad side of the hook jaw and is bent at 26 to provide;a portion .21 that embraces the other edge opposite the side 23. Theend 27 of the strap part 25 beyond the bend 25 is again curved to fitthe edge of the hook. jaw. It also provides a pad for the spring [9 toseat against. Thus, the spring i9 presses against the force of thespring tongue It on the guide member 18, and neither presses the hookjaw, thus leaving it free to slide.

As can best be seen in Fig. 3, the spring combination is disposed inproperly formed recesses in the housing. They engage the shank of thehook jaw and hold it so that it is capable of movement in both forwardand backward directions over the heel jaw 15 at the same time its fitwith the shank is sufliciently loose that the shank is free to slidelongitudinally, under control of the adjusting nut IE, to enable thehook jaw to be moved toward and away from the heel jaw.

In order to retain the main spring member in place, the housing isprovided with a recess which includes a top portion that terminates in ashoulder 30 and an enlarged intermediate portion 3! extending for a zoneopposite the main part of the tongue it. The side wall is also recessedat 32 to receive the part 25.

In operation the engagement of the part 25 with the recess 32 holds thespring in place and allows the hook jaw to be moved freely. When thewrench is engaged with a pipe, to turn the pipe, the hook jaw pivots inthe housing, the teeth moving to the left opposite the heel jaw asviewed in Fig. 3.

This pivot action takes place largely at the lower end of the housing atthe point indicated by the arrow X. Resistance to the pivoting action isprovided by the combination of the two springs. Pivoting is alsofacilitated by the nut I6 which engages with the bottom of the housing.

It will be noted that this action can occur until the shank 22 engageswith the side of the housing at the heel jaw. At this point, anotheradvantage of the spring is observed. The upper bridging portion -23 ofthe main spring provides a fiat hardened arcuate surface which shieldsthe housing and the shank of the hook jaw from each other since itengages with the housing just above the shoulder 30. It thereforeprevents wear of the housing but also protects the threads on the shankof the hook jaw from being mutilated during rough usage and when thehook jaw is extended so far that the threads are opposite the bridgepart 23, which frequently occurs.

Another advantage is also realized at this time. When the hook jawstarts to pivot in the housing, the main resistance to the pivotingeffort is the tongue [3. As can be seen the recess 3i in the housingpermits free bending or bowing of the tongue, between its ends, into therecess. This enables the tongue to retain its resiliency over a muchlonger period of time than was heretofore possible.

Although the wrench is intended to be used as a wrench and not intendedto be used to strike blows with, it frequently is used in a manner forwhich it was not intended. The workman usually hammers with the wrenchagainst a pipe or other object, causing an impact against the edge ofthe wrench below the heel jaw and opposite the housing. This causes aviolent pivoting of the hook jaw in the housing. At this time, it willbe appreciated that the bridge 23 is most desirable for protecting theparts, and what is important is the fact that the recess 3i particularlyat the juncture of the tongue it with the body 23 prevents the hook jawfrom hammering the bend out of th tongue and thus causing it to lose itsdesired form.

It will thus be seen that by my improved construction I have provided awrench, the parts of which are now economical to manufacture andassemble, and where protection for the parts is provided because of theinbent construction and which constitutes an improvement over the priorart.

Having thus described my invention, I am aware that numerous andextensive departures may be made therefor without departing from thespirit thereof as defined by the appended claims.

I claim:

1. In a pipe wrench having a handle with a heel jaw at one end and ahook jaw housing adjacent the heel jaw, said housing having an openingtherethrough substantially parallel to the handle and a hook jaw havinga threaded shank extending through said opening and a jaw disposed overthe heel jaw, the opening in the housing being sufiiciently large topermit pivoting action of the hook jaw in the housing, the improvementwhich comprises spring means for holding the hook jaw shank centered inthe housing and comprising a longitudinally extending portion shaped forclose sliding engagement with a front surface of the hook jaw shank, anarm portion extending transversely from one side of said longitudinalportion so as to lie along a side surface of the shank, and terminatingin a curved end engaging a rear surface of the shank, said longitudinalportion being provided with a tongue spaced from an upper and from bothside edges of said longitudinal portion, and sloping outwardly from ajuncture line spaced below said arm portion, the spacing of said tonguefrom the upper and side edges of said longitudinally extending portionproviding side strips connected by a bridge, said bridge holding theside strips in alignment, and said bridge being disposed between thefront surface of said shank and a front interior wall of said housing,whereby said bridge may serve as a buffer during said pivoting action ofthe hook jaw.

2. In a pipe wrench as recited in claim 1, said housing interior wallconfronting said tongue and being provided with a recess extending fromabove the tip of the tongue to a point below the juncture of the tonguewith said longitudinally extending portion, and said recess havingsufiicient depth and width to provide for fiexure of the tongue into therecess during said pivoting action.

References case in the file or this patent UNITED STATES PATENTS NumberName Date 1,727,623 Thewes Sept. 10, 1929 1,939,798 Thewes Dec. 19, 19332,192,702 Wright Mar. 5, 1940 2,302,633 Ingwer et a1 Nov. 1'7, 1942

